data recovery software

About

When drives and storage media become unreadable by the usual methods, it is often possible to recover data using specialized software.

Damaged data generally falls into one of two categories, which we'll arbitrarily designate as "rescue" and "recovery":

rescue: the directory listing can be read, and filesystem-checking utilities (such as scandisk in Microsoft Windows and fsck in Linux) report no errors, but attempting to read files results in error messages, time-outs, or bad data
recovery: directory listings are unavailable or damaged

Different software is appropriate depending on which of the two situations is occurring.

(directories ok, files/data bad)

SpinRite is an excellent tool for recovering damaged data on otherwise apparently-healthy drives. (Proprietary; ~$90)
Stellar Phoenix Partition Recovery (Proprietary; ~$100)

(directories bad, raw data readable)

dares: for CDs/DVDs only; attempts to identify known file types; does not recover directory info
testdisk: looks for munged partitions, lets you adjust partition table
- PhotoRec is part of the testdisk package, and can extract files from raw data by looking for known headers. home page